jointhefediverse.net seems to be a commonly linked resource for directing people to join the Fediverse.
Curiously, it does not list Lemmy under the list of Reddit alternatives. Their GitHub README explains why.
Previous relevant discussion: https://lemmy.ml/post/78808
It’s kind of a tradeoff. As much as I like Mbin, it’s not at feature parity with Lemmy yet, having only one mobile app is probably a deal breaker to a lot of users.